Production of acetylene



Patented Jan. 17, 1933 UNITED STATES HANS HAEUBER AND EDUARD LINOKH, bl LUDWIGSHAFEN-ON-THE-RHINE, GERMANY,

ASSIGNORSTO I. G. FABBENINDUSTRIE AKTIENGESELLSCHAIT, OF FRANKFURT-ON- THE-MAIN, GERMANY IPRODUCTION OF ACETYLENE No Drawing. Application filed December 16, 1930, Serial Nth 502,857, and in Germany December 21, 1929.

The present invention relates to the production of acetylene.

It is already known that small amounts of acetylene are formed by the incomplete combustion of aliphatic hydrocarbons, such as paraflins, olefines or gases which contain these hydrocarbons. Acetylene may also be obtained, interalia. by passing the said hydroethylene, propylene or butylene or gaseous hydrocarbons of paraffinic nature, such as methane, ethane, propane or butane or gases containing the same or mixtures of the same by employing free elementary silicon or substances containing free elementary silicon as the catalyst, which is preferably heated electrically or which may be in the form of 1101- low cylinders through which hot gases are passed, and by mixing with the hydrocarbons an amount of free oxygen or gases containing free exygen which is insuflicient for a complete combustion to carbon dioxide and water. The acetylene in the final gas may be recovered from the reaction product in any known or suitable manner or the latter may be employed directly for chemical conversions, such as. combination with oxygen, for example the synthesis of acetaldehyde. The process may (be carried out at atmospheric, reduced or somewhat elevated pressures, but it is preferable to work at from 0.5 to 5 atmospheres. High pressures of more than about 10 atmospheres will usually be avoided during the partial combustion owing to the tendency of acetylene to polymerization. The process is usually carried out at temperatures above 700 C., for example at temperatures between 800 and 1100 C.

tain about from 7 5 to 80 per cent of free silicon- Hydrogen or extraneous gases, such as nitrogen may also be present or added.

The acetylene may be recovered, for example by Washing the reaction product with a solvent such as cyclohexanone or acetone.

The following examples will further illus trate the nature of this invention, but the invention is not restricted to these examples. The percentages are by volume.

Ewample 1 A gas mixture, up to 90 per cent of which consists of propane and butane the remainder being composed of nitrogen, hydrogen, carbon dioxide and a little (about 1 to 2 per cent) of methane, is led through a quartz tube having an internal diameter of about 30'millimetres. A cylinder 5 millimeters thick consisting of pressed silicon powder is built into the tube transversely to the gas current.- This cylinder is heated electrically to a temperature of between about 850 and 900 0.. the supply of current preferably being effected centrally in openings bored in the end surfaces. A quartz tube concentrically arranged to the first mentioned tube and having an internal diameter of about 5 millimetres which is pressedout flat at the opening and through which the air or oxygen is introduced, ends directly in front of the catalyst, so that an incomplete combustion takes place on the catalyst. No deposition of carbon can be detected.

After the course of one hour 27 litres of final gas containing 7 per cent of acetylene,

, Ewample 2 A gas consisting of up to 25 per cent of olefines, up to 15 per cent of hydrogen and up to per cent of methane is led past a silicon body heated in the manner described in Example 1 together with air in the apparatus described in Example 1.

From 20 litres of initial gas and 4.8 litres of air 25 litres of a final gas containing 8.6 per cent of acetylene are obtained. 13.5 per cent of the hydrocarbons employed are therefore converted into acetylene.

lVhat we claim is 1. In the production of acetylene by incomplete combustion of a gas comprising a gaseous hydrocarbon with a gas comprising free oxygen, the step which comprises eflt'ecting the said combustion in the presence of? free elementary silicon.

2. In the production of acetylene by incomplete combustion of a gas comprising a gaseous hydrocarbon of the aliphatic scrles with a gas comprising free oxygen, the step which comprises effecting the said combustion in the presence of free elementary silicon.

3. In the production of acetylene by incomplete combustion of a gas comprising a gaseous hydrocarbon of the aliphatic series and hydrogen with a gas comprising free e 'iygen, the step which comprises eiiecting the said combustion in the presence of free elementary silicon.

4. The process for the production of acetylene, which comprises passing a gas mixture comprising'propane, butane and free oxygen into contact with free elementary silicon, while maintaining a temperature of between 700 and 1100 C.

5. The process for the production of acetylene, which comprises passing a gas mixture comprising propane and butane, and simultaneously from another source free oxygen, into contact 'with free elementary silicon, while maintaining a temperature of between 850 and 900 C.

6. The process for the production of acetylene, which comprises passing a gas mixture comprising an olefine together with free oxy gen into contact with free elementary silicon, while maintaining a temperature ofbetween 700 and 1100 C.

7 The process for the production of acetylene, which comprises passing a gas mixture 7 comprising an olefine together with free oxygen into contact with free elementary silicon, while maintaining a temperature of between 850 and 900 C.

In testimony whereof we have hereunto set our hands.

HANS HAEUBER. I EDUARD LIN CKH. 

